[1] Stavanger Univ Hosp, Dept Psychiat, N-4068 Stavanger, Norway
[2] Stavanger Univ Hosp, Dept Neurol, N-4068 Stavanger, Norway
[3] Stavanger Univ Hosp, Norwegian Ctr Movement Disorders, N-4068 Stavanger, Norway
[4] Univ Oslo, Akershus Univ Hosp, Div Mental Hlth Serv, N-1478 Lorenskog, Norway
[5] Univ Oslo, Inst Clin Med, N-1478 Lorenskog, Norway